Inlet Device for a Catalytic Converter

ABSTRACT

An inlet device for a catalytic converter is disclosed, which includes an inner shell, an outer shell and a flange. The inner shell, outer shell and flange each have a fastening end with a fastening opening. The flange is arranged at least partially between the inner shell and outer shell and fastened to the inner shell by a first connection between an outer surface of the inner shell and a front face on the flange, and to the outer shell by a second connection different from the first one between an outer surface of the flange and a front face of the outer shell.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to German Patent Application No. 102017001444.2, filed Feb. 15, 2017, which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present disclosure pertains to an inlet device for a catalytic converter.

BACKGROUND

Catalytic converters are used in motor vehicles in order to treat the exhaust gases emitted by an internal combustion engine built into the motor vehicle before these gases are released into the environment from an exhaust system. A catalytic converter here typically has an inlet device through which the untreated exhaust gases from the internal combustion engine are introduced into the catalytic converter, for example through a manifold or turbocharger, as well as an outlet device through which the exhaust gases treated by the catalytic converter are discharged into the exhaust system.

Known inlet devices for catalytic converters typically have an inner shell, an outer shell and a flange. The inner shell, outer shell and flange are joined together by a single connection. However, such conventional inlet devices are prone to breaking, resulting in a relatively short service life.

SUMMARY

In accordance with the present disclosure, an improved inlet device is provided for a catalytic converter. In an embodiment of the present disclosure, an inlet device for a catalytic converter includes an inner shell, an outer shell and a flange. The inner shell, outer shell and flange each have a fastening end with a fastening opening. The flange is arranged at least partially between the inner shell and outer shell and is fastened to the inner shell by a first connection and to the outer shell by a second connection different from the first connection.

In particular, the inlet device is used to guide exhaust gases from the internal combustion engine toward the catalytic converter. The inlet device has an inner shell and an outer shell, each which may, for example, be configured like a sphere, half-sphere, spherical segment, spherical layer, truncated cone, truncated pyramid or rotational ellipsoid. The inlet device is hollow so that exhaust gases can flow therethrough. The inner shell and outer shell typically have a thin outer wall in comparison to the hollow body. The outer shell here surrounds or encloses the inner shell at least partially at the fastening end. A hollow space is formed between the outer shell and inner shell. An insulating material can be arranged at least partially in the hollow space between the outer shell and inner shell, which insulates against heat and/or noises relative to the environment. The inner shell here typically comes into direct contact with the exhaust gas to be guided, while the outer shell primarily serves as insulation.

The inner shell and outer shell each have a fastening end and a transition end. The fastening end has a fastening opening and the transition end has a transition opening. For example, the fastening end can be arranged in a direction toward the internal combustion engine, and the transition end in a direction away from the internal combustion engine. Expressed differently, the fastening end of the inner shell and outer shell lies upstream, and the transition end lies downstream from the internal combustion engine to a muffler of an exhaust system. The shape of the outer shell and inner shell typically narrows from the transition end to the fastening end, at least in a partial section. The transition end of the inner shell and outer shell can be arranged directly on the catalytic converter, and guides the exhaust gases from the inlet device further into the catalytic converter.

A flange is used to connect the inner shell and outer shell, and hence the catalytic converter, with part of an exhaust system between the internal combustion engine and catalytic converter, for example a manifold, turbocharger or a Y-branch pipe. For example, the flange may be configured as a ring, cylinder or square, and is hollow, so that exhaust gases can flow therethrough. The flange typically has a thin outer wall by comparison to the hollow body. The flange in turn has a fastening end and a transition end. The fastening end has a fastening opening and the transition end has a transition opening. The transition end is here arranged in a direction toward the internal combustion engine, and the fastening end in a direction away from the internal combustion engine. Expressed differently, the fastening end of the flange lies downstream and the transition end lies upstream in the flow of exhaust gases from the internal combustion engine to a muffler of the exhaust system. The transition end can here be fastened to a manifold or Y-branch pipe of an internal combustion engine.

For example, the inner shell, outer shell and flange are made out of a metallic material, in particular out of a material whose temperature characteristics make it suitable long-term for the exhaust gas temperatures.

The flange is arranged at least partially between the inner shell and outer shell. The fastening end of the flange can here be arranged directly on the fastening ends of the inner shell and outer shell. At least part of the fastening end of the flange typically extends into the hollow space between the inner shell and outer shell at its fastening end.

The flange is fastened to the inner shell by a first connection and to the outer shell by a second connection different than the first one. The first and second connections can here be point-like or at least partially continuous. For example, the first and/or second connection may be configured as one or several welding points or as an at least partially continuous weld seam. Alternatively, the first and/or second connection may also be configured as one or several adhesive points or a partially continuous adhesive seam. The first and/or second connection may be a non-detachable connection, which cannot be undone without being damaged.

In particular, the advantage to this inlet device is that, by comparison to conventional inlet devices, it is especially robust and durable over a long period of time.

The inlet device may be further developed by having the fastening ends of the inner shell, outer shell and flange each have an outer surface, an inner surface and a front face. The first connection is arranged between the outer surface of the inner shell and the front face of the flange, and the second connection is arranged between the outer surface of the flange and the front face of the outer shell.

The front face of the inner shell and outer shell in the direction toward the internal combustion engine (upstream) is here arranged on the fastening end of the inner shell or outer shell, while the front face of the flange in the direction toward a muffler of the exhaust system (downstream) is arranged on the fastening end of the flange. Expressed differently, the front face of the flange faces in an opposite direction as the front faces of the inner shell and outer shell. The fastening opening is here arranged within the inner surfaces of the inner shell, outer shell and flange. The advantage to this further development is that material tensions between the inner shell and outer shell are reduced.

The inlet device can be further developed by having the outer shell at least partially cover the first connection. The outer shell may here at least partially or even completely envelop the first connection. The advantage to this further development is that the first connection is protected especially well against outside influences, such as moisture or dirt.

The inlet device can also be further developed by having the fastening opening of the inner shell have a first cross sectional shape with a first cross sectional dimension, having the fastening opening of the outer shell a second cross sectional shape with a second cross sectional dimension, and having the fastening opening of the flange a third cross sectional shape with a third cross sectional dimension. The first, second and third cross sectional shapes are similarly shaped, while the first, second and third cross sectional dimensions are different. A cross sectional shape refers to the shape which the fastening opening has when viewed from above through the opening. For example, the first, second and third cross sectional shapes may be round, circular, oval or semicircular in design. The sectional shapes may also be square, in particular rectangular or quadratic, triangular or polygonal, each with or without rounded corners.

A cross sectional dimension refers to the dimension or length which the fastening opening has when viewed from above through the opening. For example, in a circular cross sectional shape, the cross sectional dimension would be the diameter. In a quadratic cross sectional shape, the cross sectional dimension would be the diagonal between two opposite corners, for example. The advantage to this further development is that a particularly good adjustment of the flange to the inner shell and outer shell can be achieved.

The inlet device can be further developed by having the cross sectional dimension of the fastening opening of the flange be smaller than or equal to the cross sectional dimension of the fastening opening of the outer shell, and larger than or equal to the cross sectional dimension of the fastening opening of the inner shell. For example, the outer surface of the fastening end of the flange is here smaller than or equal to the inner surface of the fastening end of the inner shell, and the inner surface of the fastening end of the flange is larger than or equal to the outer surface of the fastening end of the outer shell. The advantage to this further development is that an especially good accuracy of fit can be achieved between the inner shell, flange and outer shell.

Another embodiment indicates a catalytic converter system including an inlet device according to at least one of the embodiments described above, an outlet device as well as a catalytic converter. Another embodiment indicates a motor vehicle including an internal combustion engine and a catalytic converter arrangement according to the above embodiment. As regards the advantages to the further embodiments, reference is made to the aforementioned advantages relating to the inlet device, so that the latter will not be explained yet again so as to avoid repetitions.

An inlet device described above for a catalytic converter can be manufactured in a method which includes providing an inner shell, providing an outer shell, providing a flange, arranging the flange on the inner shell, connecting the flange with the inner shell by means of a first connection, arranging the outer shell on the flange, and connecting the flange with the outer shell by means of a second connection different from the first one.

In order to implement the aforementioned method, the outer shell can be provided in a form already split into two parts, for example, or alternatively be provided in one part, and be separated into two parts before the outer shell is arranged on the flange. The separation of the outer shell here extends along a longitudinal direction through the opening of the outer shell. After arranging the outer shell in two parts, a connection joins the latter together into an integral form.

The method can also be further developed by establishing the first connection between the front face of the flange and outer surface of the inner shell. The method can be further developed by establishing the second connection between the outer surface of the flange and front face of the outer shell. As regards the advantages, variants and implementation details of this exemplary method, reference is made to the above specification about the corresponding device features so as to avoid repetition.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements.

FIG. 1 is a schematic outer view of a catalytic converter with an inlet device;

FIG. 2 is a schematic side view of an inlet device as known from prior art;

FIG. 3 is a schematic side view of an inlet device according to an embodiment of the present disclosure;

FIG. 4 is a detailed view of FIG. 3; and

FIG. 5 is a flowchart for an embodiment of a method according to the present disclosure.

DETAILED DESCRIPTION

The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background of the invention or the following detailed description.

FIG. 1 presents a schematic outer view of a catalytic converter arrangement 1 including a catalytic converter 10, an inlet device 100 as well as an outlet device 200. The inlet device 100 includes an inner shell (not shown in FIG. 1), an outer shell 120 and a flange 130. The outer shell 120 has a fastening end 121 and a transition end 129. The flange 130 likewise has a fastening end (not shown in FIG. 1) and a transition end 139. The flange 130 has a fastening opening 132, which has a circular cross sectional shape 137. The outer shell is shaped at least partially like a spherical layer, and the flange at least partially like a ring.

FIG. 2 presents a schematic sectional view of a conventional inlet device 900 having an inner shell 910, an outer shell 920 as well as a flange 930. The inner shell 910, outer shell 920 and flange 930 are here joined together with a single connection 960. An insulating material 990 is at least partially arranged between the inner shell 910 and outer shell 920.

FIG. 3 presents a schematic side view of an inlet device 100 according to an embodiment of the present disclosure. This inlet device 100 has an inner shell 110, an outer shell 120 as well as a flange 130. The inner shell 110, outer shell 120 and flange 130 here each have a fastening opening 112, 122, 132, respectively having a first, second and third cross sectional dimension 116, 126, 136. The third cross sectional dimension 136 (of the flange 130) is here larger than the first cross sectional dimension 116 (of the inner shell) 110 and smaller than the second cross sectional dimension 126 (of the outer shell 120). The flange is fastened to the inner shell 110 by means of a first connection 140, and to the outer shell 120 by means of a second connection 150 different from the first one. An insulating material 190 is at least partially arranged between the outer shell 120 and inner shell 110.

FIG. 4 presents a detailed view of an inlet device according to an embodiment of the present disclosure. As evident therein, the inner shell 110, the outer shell 120 as well as the flange 130 each have a fastening end 111, 121, 131 and a transition end 119, 129, 139. The fastening end 131 of the flange 130 is here partially arranged between the fastening end 111 of the inner shell 110 and the fastening end 121 of the outer shell 120. The inner shell 110, outer shell 120 and flange 130 further each have an outer surface 113, 123, 133, an inner surface 114, 124, 134 and a front face 115, 125, 135. The fastening end 131 of the flange 130 is here arranged between the inner surface 124 of the outer shell 120 and the outer surface 113 of the inner shell 110. The flange 130 is fastened to the inner shell by a first connection 140. This first connection 140 is arranged between the front face 135 of the flange 130 and the outer surface 113 of the inner shell 110. The flange 130 is further fastened to the outer shell 120 by a second connection 150 different from the first one. This second connection 150 is arranged between the front face 125 of the outer shell 120 and the outer surface 133 of the flange 130. An insulating material 190 is at least partially arranged between the outer shell 120 and inner shell 110.

FIG. 5 presents a flowchart for an embodiment of the method according to the present disclosure. An inner shell is here provided in the first step 1001, an outer shell is provided in the second step 1002, and a flange is provided in the third step 1003. The flange is then arranged on the inner shell in the next step 1004, and then joined with the inner shell by a first connection in an ensuing step 1005. This is followed by an optional step 1006, in which the outer shell is divided into two parts, provided the latter has not already been provided in two parts. The two-part outer shell is arranged on the flange in the next step 1007. The flange is joined with the outer shell by means of a second connection different from the first one in the following step 1008, and the outer shell is joined into one piece by a connection in the last step 1009.

While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the various embodiments in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment as contemplated herein. It being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the various embodiments as set forth in the appended claims. 

1-10. (canceled)
 11. An inlet device for a catalytic converter comprising: an inner shell having a first fastening end defining a first opening; an outer shell having a second fastening end defining a second opening, wherein the outer shell at least partially surrounds the inner shell; a flange having a third fastening end defining a third opening, wherein the third fastening end is at least partially arranged between the first and second fastening ends; a first connection fastening the inner shell to the flange; and a second connection, which is separate from the first connection, fastening the outer shell to the flange.
 12. The inlet device according to claim 11, wherein the first connection is arranged between a first outer surface of the inner shell and a third front face of the flange, and the second connection is arranged between a third outer surface of the flange and a second front face of the outer shell.
 13. The inlet device according to claim 11, wherein the first connection comprises a first welded joint between the first outer surface of the inner shell and the third front face of the flange, and the second connection comprises a second welded joint between the third outer surface of the flange and the second front face of the outer shell.
 14. The inlet device according to claim 11, wherein the outer shell at least partially covers the first connection.
 15. The inlet device according to claim 11, wherein the first fastening opening defines a first cross sectional shape with a first cross sectional dimension, the second fastening opening defines a second cross sectional shape having a second cross sectional dimension, and the third fastening opening defines a third cross sectional shape having a third cross sectional dimension, wherein the first, second and third cross sectional shapes are similarly shaped, and the first, second and third cross sectional dimensions are different.
 16. The inlet device according to claim 14, wherein the third cross sectional dimension is less than or equal to the second cross sectional dimension and greater than or equal to the first cross sectional dimension.
 17. The inlet device according to claim 11, further comprising an insulating material disposed between the inner and outer shell.
 18. A catalytic converter arrangement comprising: a catalytic converter having a housing with an inlet and an outlet; an inlet device according to claim 11 arranged in the inlet of the catalytic converter; and an outlet device arranged in the outlet of the catalytic converter.
 19. An inlet device for a catalytic converter comprising: an inner shell having a first fastening end defining a first opening having a first cross sectional shape with a first cross sectional dimension; an outer shell having a second fastening end defining a second opening having a second cross sectional shape with a second cross sectional dimension, wherein the outer shell at least partially surrounds the inner shell; a flange having a third fastening end defining a third opening having a third cross sectional shape with a third cross sectional dimension, wherein the third fastening end is at least partially arranged between the first and second fastening ends; a first welded joint arranged between a first outer surface of the inner shell and a third face of the flange to fasten the inner shell to the flange, wherein the outer shell at least partially covers the first connection; and a second welded joint arranged between a third outer surface of the flange and a second face of the outer shell to fasten the outer shell to the flange, wherein the second front face is longitudinally offset from the third face such that second welded joint is different from the first welded joint; wherein the first, second and third cross sectional shapes are similarly shaped, and the first, second and third cross sectional dimensions are different.
 20. A method for manufacturing an inlet device for a catalytic converter comprising: providing an inner shell arranging an inner surface of a flange on an outer surface of the inner shell; forming a first connection between the outer surface of the inner shell and a front face of the flange; arranging an inner surface of an outer shell on an outer surface of the flange such that the outer shell at least partially surrounds the inner shell; and forming a second connection between the outer surface of the flange with the a front face of the outer shell, wherein the second connection is different from the first connection.
 21. The method according to claim 19, wherein forming a first connection comprises forming a first welded joint between the outer surface of the inner shell and the front face of the flange, and forming a second connection comprises forming a second welded joint between the outer surface of the flange with the a front face of the outer shell.
 22. The method according to claim 19, further comprising disposing an insulating material between the inner and outer shells. 